experimental: renderer

lua/u/utils/string.lua

@@ -0,0 +1,29 @@
+local M = {}
+
+--------------------------------------------------------------------------------
+--- eat_while
+--------------------------------------------------------------------------------
+
+--- @param s string
+--- @param pos number
+--- @param predicate fun(c: string, i: number, s: string): boolean
+function M.eat_while(s, pos, predicate)
+  local eaten = ''
+  local curr = pos
+  local watchdog = 0
+  while curr <= #s do
+    watchdog = watchdog + 1
+    if watchdog > #s then error 'infinite loop' end
+
+    local c = s:sub(curr, curr)
+    if not predicate(c, curr, s) then break end
+    eaten = eaten .. c
+    curr = curr + 1
+  end
+  return eaten, curr
+end
+
+--- @param c string
+function M.is_whitespace(c) return c == ' ' or c == '\t' or c == '\n' end
+
+return M